Plants Have Future As Environmental Clean-Up Agents

MANHATTAN -- It's a problem occurring across the country.
Hazardous chemicals left behind in landfills and dump sites threaten
water supplies and health. Clean-up is expensive and time-consuming.

But research at Kansas State University into a process known as
plant-based bioremediation is showing that an answer to those
problems could be helped by something as simple as planting a tree.

"Essentially, bioremediation is using organisms to clean up
contaminants," said Larry Davis, professor of biochemistry. "Usually
it means bacteria or fungi-emphasizing plants which are present in
the root zone."

In essence, the vegetation serves as a pump bringing contaminated
water close to the surface. Depending on the type of chemical
present, bacteria on the plant roots can feed on some types of
chemicals, while other chemicals are brought closer to the surface,
which can hasten their degradation because oxygen is present.

"In some cases, we have actually seen 10 pounds per acre a day
removed," Davis said. "It really depends on what's present there."

In either case, using plant-based bioremediation is cheaper then
more traditional methods of clean-up such as pumping and treating or
excavation, according to Larry Erickson, professor of chemical
engineering.

"I would say society is going to save many millions of dollars,"
he said. "We're finding the use of vegetation has use in a number of
environments and a number of problems."

That's hopefully going to be the case in Riley County, which is
the home county of both K-State and the city of Manhattan. Facing
clean-up costs at a closed landfill, they drew on K-State's expertise
in the area of bioremediation for a solution.

Drawing on work by both students and faculty, the county decided
to adopt bioremediation as a solution. This spring, 5,000 poplar
trees will be planted at the site.

"It's really an application of university research to a county
level," said Ann Feyerharm, special projects assistant for Riley
County. "I never would have heard of it if it hadn't been for Dr.
Erickson and Dr. Davis."

Feyerharm said one of the most attractive aspects of
bioremediation to Riley County was the cost. Traditional clean-up
methods could have cost an estimated $4 million in the first year,
and $8 million over 20 years. The total cost of the bioremediation is
expected to be around $15,000.

But the aesthetic qualities of bioremediation were also an
attraction. Feyerharm said the planting of the trees will help
control erosion problems and attract wildlife, something traditional
treatments wouldn't do.

"We think this a no lose opportunity for us," Feyerharm said.

Erickson and Davis, along with other K-State professors, are
continuing research into bioremediation, both in areas of genetic
research and practical application. The Great Plains/Rocky Mountain
Hazardous Substance Research Center, a consortium of 14 universities
with headquarters at K-State, funds a number of bioremediation
research projects across the country.

Considering there are approximately 300,000 sites across the
United States in need of clean-up, many are hoping research will lead
to a cleaner environment.

"We're doing some cutting edge work," Erickson, who serves as
director of the center, said. "One of our goals is to bring useful
technology to the field.

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